Bathtub copper trap replacement.

I'm replacing a 30" wide tub with a 34" wide tub in a circa 1969 house. The current tub is using a copper 1 1/2" drain trap soldered into the waste/vent line. I can't move or even pivot the triple inlet (drain/drain/vent) on the waste/vent line because another tub on the other side of the wall is using it as well. My question is, do they make copper U traps of different distances between the openings? IE: the existing U trap has openings 2 3/4" on center - I looks like I would need a U trap of 4 3/4" to 5" on center to position correctly for the new tub.